A Retrospective Comparative Evaluation of Selected Blood Cell Ratios, Acute Phase Proteins, and Leukocyte Changes Suggestive of Inflammation in Cats

Abstract

Neutrophil-to-lymphocyte (NLR), monocyte-to-lymphocyte (MLR), and platelet-to-lymphocyte (PLR) ratios have been proposed as diagnostic and prognostic markers for neoplastic and inflammatory diseases in dogs and cats. The aim of this retrospective preliminary study was to evaluate the relationship between these ratios and markers of inflammation routinely measured in cats. A total of 275 cats were enrolled. Complete blood count, serum amyloid A (SAA), albumin, globulin, and albumin-to-globulin ratio (AGR) data were analyzed, as well as the presence of leukocyte alterations considered suggestive of inflammation (LAI: neutrophils left shift, toxic neutrophils, and reactive lymphocytes) evaluated in blood smears. The NLR and MLR correlated positively with SAA and globulins and negatively with albumin and AGR. Higher NLR and MLR were found in cats with increased SAA and globulins and decreased albumin and AGR. The PLR correlated negatively with albumin and AGR. A higher PLR was found in cats with hypoalbuminemia. Cats with LAI had higher NLR, MLR, and PLR. In cats with no changes in parameters indicative of inflammation, 11.25, 0.42, and 528.3 were identified as upper limits for NLR, MLR, and PLR, respectively. In conclusion, the NLR, MLR, and PLR act as good inflammatory markers easily evaluated by routine hematology.

Hemogram-Derived Inflammatory Markers in Cats with Chronic Kidney Disease

“…In our study, the median NLR and MLR in healthy cats were in accordance with the literature [ 16 , 19 ], and the median PLR was slightly greater than that in previously published data [ 19 ]. Cats with advanced CKD had significantly greater levels of all investigated hemogram-derived inflammatory markers than did cats with early CKD and those in the control group.…”

“…Hemogram-derived inflammatory markers, such as NLR, MLR, PLR, and SII, have been identified as diagnostic and/or prognostic markers for various neoplastic and inflammatory diseases in cats [ 14 , 15 , 17 , 19 , 28 ], but their role in feline CKD has not yet been studied. In human CKD patients, increased values of hemogram-derived inflammatory markers were found to have predictive value for mortality in end-stage CKD patients [ 21 , 29 , 30 , 31 , 32 , 33 , 34 , 35 ].…”

“…These markers are recognized as diagnostic and prognostic markers for dogs with lymphomas, osteosarcomas, and mast cell tumors [ 15 ]. In cats, the use of hemogram-derived inflammatory markers has been reported with no inflammation, hypertrophic cardiomyopathy, feline mammary carcinomas, acute pancreatitis, feline injection site sarcomas, or high-grade lymphomas [ 14 , 15 , 16 , 17 , 18 , 19 ].…”

“…A recent study [ 23 ] reported increased NLR in cats with CKD at the end of life, which was proposed to be a consequence of the inflammatory whole-body response. Donato et al [ 19 ] reported a weak positive correlation between the NLR and MLR with serum amyloid A and globulin in healthy and diseased cats. However, cats with CKD were not included in this study.…”